Place the sliced fish fillets in a bowl with the buttermilk, salt, white pepper and garlic salt. Mix together, place in the fridge to marinate for 20-30 minutes (it doesn't need to marinate for too long as the fish is already tender).
Heat around 1 inch of oil in a large frying pan on a medium-high heat until hot. Preheat the oven to a low heat to keep the fish warm once cooked.
Mix together the fish coating ingredients (except the oil) in a bowl. Take the fish out of the fridge. Lift a piece from the buttermilk and allow the excess to drip off. Dredge the fish in the crispy coating mixture – ensuring it’s fully covered. Place on a tray and repeat until all of the fish is coated.
Place the fish pieces carefully in the oil, 4-5 pieces at a time and fry, turning once until golden and crispy (about 3-4 minutes per batch). Once cooked, removed from the oil with a slotted spoon, place on a baking tray and place in the oven to keep warm. Repeat with the rest of the fish.
Meanwhile, mix together all of the pico de gallo ingredients in a bowl.
Heat a second large frying pan on a high heat and add a tortilla to the dry pan. Cook until lightly browned, then turn over and cook the other side until lightly browned (should take around 30-60 seconds each side). Place on a plate and repeat with the rest of the tortillas.
Mix together the mayonnaise and sriracha and put to one side.
Now it's time to assemble. Place a taco on a plate and top with 2-3 pieces of the cooked fish. Spoon on a tbsp of the pico de gallo and drizzle on a little of the sriracha mayo.
Repeat until you have filled all 6 tacos, then serve immediately.
The fish coating is crispiest right after frying, so try to cook in only a couple of batches if you have a large enough pan. .
You can make the fish ahead, with the crispy batter and reheat later. Simply cook, cool, cover and refrigerate for up to a day. Then reheat in a hot (180C/360F) oven for about 10 minutes. They fish won't be quite as crispy, but it's still delicious..
Gluten Free Crispy Fish Tacos:
I haven't tried it with gluten free flour yet, but I believe this will still work well if you replace the flour with gluten free flour blend and gluten free baking powder.You'll also need to use gluten free tortillas..Nutritional Information is per taco.This info is approximate, as all of the flour may not be used up in coating the fish (I've counted all of the flour as part of the nutritional info though). Also, I've included ½ tbsp of oil per taco to account for the oil that is absorbed during deep drying (this is an *approximate* amount, the fish may absorb more or less).